package com.example.forum.interceptor;

import com.example.forum.config.AppConfig;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import jakarta.servlet.http.HttpSession;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;

/**
 * Created with IntelliJ IDEA.
 * Description: 登录拦截器
 * User: liuli
 * Date: 2024-08-13
 * Time: 14:52
 */
@Component
public class LoginInterceptor implements HandlerInterceptor {


    @Value("${forum.login.url}")
    private String defaultURL;
    /**
     *前置处理（对请求的预处理）
     * @return true：继续流程 <br/> false：流程中断
     * @throws Exception
     */

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse
            response, Object handler) throws Exception{
        //获取session对象
        HttpSession session = request.getSession(false);
        //判断session是否有效
        if(session != null && session.getAttribute(AppConfig.USER_SESSION) != null){
            //用户已经是登录状态，校验通过
            return true;
        }

        //校验url是否正确
        if(!defaultURL.startsWith("/")){
            defaultURL = "/" +defaultURL;
        }

        //校验不通过，跳转到登录界面
        response.sendRedirect("defaultURL");
        //中断流程，返回false
        return false;
    }

}
